Hi, I am having problems with my headings. I load up PMDG 747 (FS9) into London's Heathrow airport, using UK2000 scenery. I'm dead straight on the runway, i know from personal & simulation expirence that the heading should be 272. But i'm showing 275. Also when i put my departure runway, you can tell the heading's are off due to the aircraft being facing away from the white marker showing approach path for dep/arr. My SID/STAR's are all up to date using Navigraph AIRAC cycle 909. Is there something i need to re-configure?CheersJames

Hi, I am having problems with my headings. I load up PMDG 747 (FS9) into London's Heathrow airport, using UK2000 scenery. I'm dead straight on the runway, i know from personal & simulation expirence that the heading should be 272. But i'm showing 275. Also when i put my departure runway, you can tell the heading's are off due to the aircraft being facing away from the white marker showing approach path for dep/arr. My SID/STAR's are all up to date using Navigraph AIRAC cycle 909. Is there something i need to re-configure?CheersJames

You may have installed an add-on scenery that messes with magnetic/true headings. I have in the past found two that have done that, I haven't a clue why.It is painful to track them down. I would start by temporarily disabling any sceneries you know you have installed recently. If this cures it, replace them a few at a time to identify the culprit. You may even be able to identify a specific file within the scenery.John

It's a little unclear from the original post how "ground truth" is being determined. I assume OP is in slew mode so that he is looking at the actual heading of the aircraft, and not trying to analyze the ground track after winds/aircraft asymmetry is applied.The magnetic heading of the aircraft, as shown in the whiskey compass, or slaved gyro, is computed by applying the local magnetic variation from the magdec.bgl file to the true heading (longitudinal axis) of the aircraft. The computation can be examined using addon gauges or tools such as AFSD which show true heading and mag var at the aircraft location. So using this you should be able to see if FS is generating the right mag heading. I have seen scenery files that cause errors, but I have never seen it vary by just a couple degrees -- more like 180 out. (VOR radials are computed using the magvar attribute from the VOR bgl code, not the prevailing magdec.bgl data -- may differ, I think the VOR data is obtained from a Jepps database).Note that the magdec.bgl file might be off a couple degrees from what a chart might show, since AFAIK magdec.bgl is based on the 2005 epoch.edit: I think the 2005 epoch is for FSX and FS9 was 2000!scott s..

It's a little unclear from the original post how "ground truth" is being determined. I assume OP is in slew mode so that he is looking at the actual heading of the aircraft, and not trying to analyze the ground track after winds/aircraft asymmetry is applied.The magnetic heading of the aircraft, as shown in the whiskey compass, or slaved gyro, is computed by applying the local magnetic variation from the magdec.bgl file to the true heading (longitudinal axis) of the aircraft. The computation can be examined using addon gauges or tools such as AFSD which show true heading and mag var at the aircraft location. So using this you should be able to see if FS is generating the right mag heading. I have seen scenery files that cause errors, but I have never seen it vary by just a couple degrees -- more like 180 out. (VOR radials are computed using the magvar attribute from the VOR bgl code, not the prevailing magdec.bgl data -- may differ, I think the VOR data is obtained from a Jepps database).Note that the magdec.bgl file might be off a couple degrees from what a chart might show, since AFAIK magdec.bgl is based on the 2005 epoch.edit: I think the 2005 epoch is for FSX and FS9 was 2000!scott s..

Hi, I was told do use this patch to fix the error by PMDG - ( http://ops.precisionmanuals.com/wiki/How_t...Tracking_Errors )Seemed like a easy 100% fix, installed it but are having the same problem, i also un-installed UK2000 LHR, so i'm currently using Defult LHR. And have the same problem!Your help is needed!CheersJames Andrews

Hi, I was told do use this patch to fix the error by PMDG - ( http://ops.precisionmanuals.com/wiki/How_t...Tracking_Errors )Seemed like a easy 100% fix, installed it but are having the same problem, i also un-installed UK2000 LHR, so i'm currently using Defult LHR. And have the same problem!Your help is needed!CheersJames Andrews

I should also state i'm getting heading area's at all airports and all aircrafts!

I should also state i'm getting heading area's at all airports and all aircrafts!

Anyone ?

Something else you need to think about is I have noticed several aircraft that have heading problems and one cure for this is to press the d key this will adjust the heading. If you use flying tips it will tell you when there is a problem about this. I have never figured out why only several aircraft have this problem but they do. I m fairly certain that it is not a gauge problem. It could be in the air file or the aircraft cfg file Not really sure. That is my main reason to fly with flying tips on it lets you know about odd things like that. :(

Some aircraft are fitted with a basic directional gyro. A DG is not "north seeking" but rather remains more or less fixed, but is subject to drift. It is necessary to compare the gyro to the magnetic compass periodically and reset it. That's what the D key does for you automatically. In more advanced aircraft (typically when an HSI is installed, but not necessarily) the DG is "slaved" to a magnetic sensing unit mounted in the wing, so that it is continuously reset to north. The slaved gyro is indicated in the aircraft.cfg file, for example the default Baron:

[direction_indicators]//1 Type: 0=None, 1=Vacuum Gyro, 2=Electric Gyro, 3=Electro-Mag Slaved Compass, 4=Slaved to another//2 Indicator number of slaving indicator if Type = 4direction_indicator.0=3,0

Note that the mag compass won't indicate correctly in a turn, but I don't know if FS9 models this or not.scott s..

Some aircraft are fitted with a basic directional gyro. A DG is not "north seeking" but rather remains more or less fixed, but is subject to drift. It is necessary to compare the gyro to the magnetic compass periodically and reset it. That's what the D key does for you automatically. In more advanced aircraft (typically when an HSI is installed, but not necessarily) the DG is "slaved" to a magnetic sensing unit mounted in the wing, so that it is continuously reset to north. The slaved gyro is indicated in the aircraft.cfg file, for example the default Baron:

[direction_indicators] //1 Type: 0=None, 1=Vacuum Gyro, 2=Electric Gyro, 3=Electro-Mag Slaved Compass, 4=Slaved to another //2 Indicator number of slaving indicator if Type = 4 direction_indicator.0=3,0

Note that the mag compass won't indicate correctly in a turn, but I don't know if FS9 models this or not.scott s.It's the heading on the PFD as well, the PMDG course runway white dotted line is off. If i approach heathrow directly on the dotted marker line. I will be heading slightly away from the runway. The runway does not line up with the white dotted course portrayed by PMDG? .

It's the heading on the PFD as well, the PMDG course runway white dotted line is off. If i approach heathrow directly on the dotted marker line. I will be heading slightly away from the runway. The runway does not line up with the white dotted course portrayed by PMDG?

That's because there's a difference between the direction of the runway in the scenery and the direction in the Navapt database file.I correct my database file to agree with the scenery I use and then there is no problem. The only problem arises if you update your nav data through Navigraph, etc. because you would lose your own amendments. Not a problem if you don't fly on-line and don't need updated data.Colin B

That's because there's a difference between the direction of the runway in the scenery and the direction in the Navapt database file.I correct my database file to agree with the scenery I use and then there is no problem. The only problem arises if you update your nav data through Navigraph, etc. because you would lose your own amendments. Not a problem if you don't fly on-line and don't need updated data.Colin B

Hi Colin, How do i correct my database file to agree with PMDG?CheersJames Andrews

First, use Afcad or ADE9X to open the uk2000 afcad for EGLL and go to Lists>Runways and check the Magnetic hdg of each runway.Then, open your wpNavApt.txt file and find the entries for EGLL. It should be similar (but not necessarily the same as mine) So...Heathrow EGLL09L12799095 51.477450 -0.489428110.3009500080Heathrow EGLL09R12001095 51.464939 -0.486772109.5009500080Heathrow EGLL27L12001275 51.464953 -0.434075109.5027500080Heathrow EGLL27R12799275 51.477675 -0.433264110.3027500080The left 095/275 should be the same as the runway in the scenery and the right 095/275 is the localiser magnetic bearing, which I make the same as the runway unless it's an offset ILS.You can also update the runway length, (12799, for 09L and 27R) and the field elevation (80), if you wish.If it still isn't correct, you need to get the runway threshold position ( again with afcad) and alter the positions above (51.477450 -0.489428 for 09L) and if necessary change the ILS position in a similar way in the wpNavaids.txt file but hopefully, that won't be necessary.The thing to remember is, if you update the files through Navigraph or such, you will lose your changes and have to redo them.Be very careful when altering entries in those files because it's important to keep the field and record lengths the same as they were, so no extra spaces and no deleting any you might think aren't necessary. Most important of all, BACKUP any file before trying this, then you can always go back to it if things go wrong.Colin B

James, just a shot into the dark, but are you aware that in the PMDG 747 you can switch between "MAG HDG" and "TRU HDG"?At some locations there is quite a difference between magnetic heading and true headingWolfgang